I have got two oak samples from just outside Linköping which I did collect already as a teenager, in the first part of the 1980'th! Measurements for them are now available at http://www.taxelson.se/dendro/HkfQ.rwl
(season wood measurements at http://www.taxelson.se/dendro/HkfQ.zip
). Cross dating values at: http://www.taxelson.se/dendro/noteringar2009.htm#2009-03-14
(in Swedish). It may be of some interest to see what correlation values could be expected from this area towards available references.